In the long term evolution infrastructure, one proposal being studied is the use of acknowledgement/negative acknowledgement (ACK/NACK) repetition in order to increase the probability of correct hybrid automatic repeat request (HARQ) feedback signal detection for more important MAC PDUs or in an uplink power limited case. These more important MAC PDUs could, for example, include those containing control information in their body or as part of the header. Discontinuous reception values are one example of control information that could be sent in a MAC PDU.
One problem with multiple acknowledgements/negative acknowledgements, hereinafter referred as multiple acknowledgements is that if messages requiring multiple feedbacks are sent in adjacent time slots, collisions between the acknowledgements may occur and the enhanced Node B could not decode the acknowledgements properly due to the collision. Avoiding adjacent time slots creates latency.